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/* See LICENSE file for copyright and license details. */
#include "internals.h"
void
zxor(z_t a, z_t b, z_t c)
{
size_t n, m;
if (zzero(b)) {
if (zzero(c))
SET_SIGNUM(a, 0);
else
SET(a, c);
return;
} else if (zzero(c)) {
SET(a, b);
return;
}
m = MAX(b->used, c->used);
n = b->used + c->used - m;
if (n == m && !zmemcmp(b->chars, c->chars, m)) {
SET_SIGNUM(a, 0);
return;
}
if (a->alloced < m)
zahl_realloc(a, m);
if (a == b) {
zmemcpy(a->chars + n, m == b->used ? b->chars : c->chars, m - n);
while (n--)
a->chars[n] ^= c->chars[n];
} else if (a == c) {
zmemcpy(a->chars + n, m == b->used ? b->chars : c->chars, m - n);
while (n--)
a->chars[n] ^= b->chars[n];
} else if (m == b->used) {
zmemcpy(a->chars, b->chars, m);
while (n--)
a->chars[n] ^= c->chars[n];
} else {
zmemcpy(a->chars, c->chars, m);
while (n--)
a->chars[n] ^= b->chars[n];
}
SET_SIGNUM(a, 1 - 2 * ((zsignum(b) ^ zsignum(c)) < 0));
}
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